This is necessary where in certain environments where
cgroup is used to limit memory usage of a container or
a particular process.
GetStats() is used by caching module to figure out the
optimal cacheable size in memory with cgroup limits
what sysinfo reports might not be the right value set
for a given process.
Fixes#4001
This API is precursor before implementing `minio lambda` and `mc` continous replication.
This new api is an extention to BucketNofication APIs.
// Request
```
GET /bucket?notificationARN=arn:minio:lambda:us-east-1:10:minio HTTP/1.1
...
...
```
// Response
```
{"Records": ...}
...
...
...
{"Records": ...}
```
